It is the long-range purpose of this project to study interactions and relationships between connective tissue macromolecules as a way to understand connective tissue formation and structure. The topics of present interest are: 1) High-resolution electron microscopy of fibrils and other aggregates of collagen. 2) The mechanism of collagen fibril formation. 3) Quasielastic light scattering. 4) Abnormal forms of collagen and other connective tissue molecules.